Filamentous fungi are useful systems for various functions and applications. Filamentous fungi, such as, for example, Aspergillus (e.g., A. niger) and Trichoderma (e.g., T. reesei) secrete a variety of cellulases and hemicellulases that hydrolyze plant-derived polysaccharides into sugar monomers which are then used as a carbon source and hence energy by the fungal cells. Accordingly, filamentous fungi are often ideal organisms for large scale industrial fermentation because of their ability to secrete fermentation products, such as, for example, heterologous proteins (e.g., swollenins, antibodies and enzymes, such as proteases, cellulases, glucoamylases, alpha amylases, xylanases, and phytases), into the culture media.
However, introduction of exogenous nucleic acids into filamentous fungus such as, for example, (i.e., transformation) has typically been a problem in constructing strains based in these hosts. Although methods for introducing exogenous nucleic acids into filamentous fungi are known (e.g., “biolistic” transformation and “protoplast-PEG” transformation) and reference is made to APPLIED MOLECULAR GENETICS OF FILAMENTOUS FUNGI, Ed., J R Kinghorn and G Turner, (1992) Chapter 1, May, G., “Fungal Technology”, pgs 1-25, Blackie Academic & Professional, UK; Sanchez et al., (1996) Fungal Genetics Newsletter 43:48-51; ELECTROPORATION PROTOCOLS FOR MICROORGANISMS (1995) Ed. J A Nickoloff, Totowa, N.J. Humana Press; Cao et al., (2000) Protein Sci. 9:991-1001; Yelton et al., (1984) Proc. Natl. Acad. Sci. USA 81: 1470-1474; and Nevalainen et al., The Molecular Biology of Trichoderma and its Application to the Expression of Both Homologous and Heterologous Genes” in MOLECULAR INDUSTRIAL MYCOLOGY, Eds. Leong and Berka, Marcel Dekker Inc., NY (1992) pp 129-148, there is still a need for additional methods that introduce nucleic acids into filamentous fungi.